2. Place the flank steak in a shallow bowl and pour the marinade over it. Cover and refrigerate for 1 hour or overnight.

3. Preheat the grill to high.

4. Grill the flank steak for 4 to 8 minutes on each side, depending on the desired doneness. Let the steak rest on a carving board before slicing.

5. Meanwhile, combine the cherry tomatoes, onion, basil, red wine vinegar and extra virgin olive oil in a small mixing bowl. Season with salt and pepper and set aside. (The tomatoes can be prepared ahead of time and stored in the refrigerator.)